Technical Abstract:
Corn stover is targeted as a potential non-food bioenergy feedstock, especially in the midwestern United States. Three parallel experiments were conducted on adjacent fields. One was managed without tillage since 1995. A second experiment was managed without tillage since 2005. The third was managed with chisel plowing since 2005. The residue removal treatments were the same in all experiments with 0, 50%, 75% and 100% of the rows from plots in the corn phase of the rotation harvested. In 2008, the 75% stover removal was changed to cob removal. The no-tillage experiment established in 2005 had stover first removed in 2006. Plant data includes yields for grain, cob and stover, the mass of residue remaining in the field, plant moisture and spring soil cover. Soybean yield was similar among residue treatments in the chisel plow and no tillage since 2005 experiments. However, in the no tillage since 1995 experiment, soybean yield decreased with increasing residue removal in 2010. Corn yield in the 2010 harvest was not altered by residue harvest. These plots were in a corn-soybean rotation. The soybean crop following stover harvest may buffer some of the immediate microclimate impacts of residue management. A brief summary of plant and soil response will be presented. [REAP Publication]